Hand tool for inserting conductors to terminals

ABSTRACT

Hand tool for inserting a conductor into a terminal which is contained in a connecting device comprises a frame having a reciprocable inserting ram therein. The frame and the ram have holding surfaces which are located and contoured such that the tool can be held in the palm of the hand and squeezed to move the ram along its inserting stroke. The tool has an improved separate holder for holding the connector and an improved full stroke compelling mechanism.

United States Patent Mayberry et al.

[ Oct. 1, 1974 HAND TOOL FOR INSERTING CONDUCTORS TO TERMINALS Inventors: Mickey Lee Mayberry, Pfafftown;

John James Tucci, Winston Salem, both of N.C.

Assignee: AMP Incorporated, Harrisburg, Pa.

Filed: July 18, 1973 Appl. No.: 380,321

U.S. Cl. 29/203 H Int. Cl. H05k 13/04 Field of Search..... 29/203 H, 203 HC, 203 HT,

References Cited UNITED STATES PATENTS 7/1973 Brehm 29/203 H 3,758,935 9/l973 Long et al 29/203 H Primary ExaminerThomas H. Eager Attorney, Agent, or Firm--AMP Inc.

Hand tool for inserting a conductor into a terminal which is contained in a connecting device comprises a frame having a reciprocable inserting ram therein. The frame and the ram have holding surfaces which are located and contoured such that the tool can be held in the palm of the hand and squeezed to move the ram along its inserting stroke. The tool has an improved separate holder for holding the connector and an improved full stroke compelling mechanism.

ABSTRACT 5 Claims, 7 Drawing Figures QBAQI EAIENIEDum 11914 sneer gm 5 HAND TOOL FOR INSERTING CONDUCTORS TO TERMINALS BACKGROUND OF THE INVENTION This invention relates to hand tools for inserting conductors into the conductor receiving portions of terminals contained in an electrical connector or the like. A previously known tool of this general type is shown in U.S. Pat. No. 3,742,571.

It is now common practice in the electrical industry to use multi-contact connecting devices which are preloaded with electrical contact terminals which have conductor-receiving portions. When the connector or other device is installed on a cable, the conductors of the cable are simply inserted into these conductorreceiving portions of the contact terminals. Connectors of this general type are shown in application Ser. No. 147,569 now U.S. Pat. No. 3,760,335 and a preferred form of apparatus for simultaneously inserting a plurality of conductors into the conductor receiving portions of the terminals is shown in application Ser. No. 147,578, now U.S. Pat. NO. 3,758,935.

There is also a requirement for an inexpensive and compact hand tool for inserting a single conductor into the conductor-receiving portion of a contact terminal. A compact tool of this type is needed by the technician who must service a previously installed connector at a work site and/or connect the conductors of a cable to the terminals in a connector at a work site. U.S. Pat. No. 3,742,571 shows one type of hand tool which is satisfactory under most circumstances however, it has been found that a tool which is more compact than the tool shown in U.S. Pat. No. 3,742,571 would be desirable. The instant invention is therefore addressed to the achievement of an improved hand tool which is more compact than those previously available and which has other improvements including a full stroke compelling mechanism which ensures that an individual conductor will be fully inserted into the conductor receiving portion of the terminal and an improved holder or jig means for the connector.

It is accordingly an object of the invention to provide an improved hand tool for inserting an individual conductor into the conductor receiving portion of a terminal contained in an electrical connector or other electrical device. A further object is to provide a tool which is convenient to use by the technician and which can be used for a prolonged period of time without undue fatigue. A further object is to provide a hand tool having a full stroke compelling mechanism which will ensure complete insertion of a conductor into a terminal, and an improved workholder for the connector or other device into which conductors are being inserted.

These and other objects of the invention are achieved in a preferred embodiment of the invention which is briefly described in the foregoing abstract is described in detail below, and which is shown in the accompanying drawing in which:

FIG. 1 is a perspective view of a preferredform of the hand tool in accordance with the invention.

FIG. 2 is a perspective view of the tool of FIG. 1 with the parts exploded from each other.

FIG. 3 is a perspective exploded view of the head portion of the tool showing details of the full stroke compelling mechanism.

FIG. 4 is a cross-sectional view of the tool showing the ram in its normal or retracted position.

FIG. 5 is a view similar to FIG. 4 but showing the positions of the parts at the completion of a conductor inserting operation.

FIG. 6 is a fragmentary perspective view of a preloaded electrical connector of the type for which the instant tool is adapted for use.

FIG. 7 is a fragmentary sectional view on an enlarged scale illustrating the manner of inserting a conductor into conductor receiving portion of a terminal in a connector.

Referring first to FIGS. 6 and 7, the disclosed embodiment of the invention is adapted to trim the end of a wire 2 and insert the trimmed wire end into an electrical contact terminal of the type shown at 4. The terminal 4 is one of a battery of terminals contained in a multi-contact electrical connector part 6 of the type fully described in the above-identified application Ser. No.

147,569, now U.S. Pat. No 3,760,335. For purposes of the instant disclosure, it should be explained that each terminal 4 has a generally U-shaped wire receiving portion 8 at its rearward end which is defined by a pair of spaced apart plate-like portions l0, 12 which are connected to each other by relatively thin strap-like sections 14. Slots 16 extend downwardly into the plate-like sections, the width of these slots being such that when the wire is forced into the slots, the edges of the slots will penetrate the wire insulation and establish electrical contact with the conducting core as illustrated in FIG. 11.

Each terminal 4 has a forwardly extending shank portion 18 and a relatively narrower contact portion 20 at its forward end. The terminals are contained in the cavities 22 in the connector 6 which cavities extend from the rearward side 24 of the connector to the forward side 28, thereof. The connector shown is the female part of the connector assembly and has a recess 26 extending inwardly from its forward side. The cavities 22 are separated by spaced-apart barrier plates 30 on the rearward face of the connector and a flange or rib 32 extends radially from the connector body mid-way between its faces. This flange defines a rearwardly facing surface 34, which is opposed to the edges of the barriers 30, and upwardly and downwardly facing ledges 36. As will be explained below, the surfaces 34 and 36 of the connector housing are utilized to locate the connector accurately in a tool in accordance with the invention.

Turning now to FIGS. 1, 2, and 4, a preferred form of tool 38 in accordance with the invention comprises a housing 40 having a ram or plunger 42 slidably contained therein. The housing is made up of a base section 44 and a cap section 46, both of these sections being formed of a suitable firm plastic material such as a nylon containing about thirty per cent glass fibers for A shallow depression 56 is provided on the upper surface 62 of main body section 54 and a T-shaped steel plate 58 is mounted on this upper surface. The head portion 61 of this plate is supported on the portions of the surface 62 which are adjacent the recess 48 so that the leading edge portion of the plate extends over the recess as shown in FIG. 1 and 4. The leg 60 of the late 61 extends rearwardly and centrally over the depression 56, and the plate is secured to the body portion of the housing by suitable fasteners 64. As indicated in FIG. 2, wherever fasteners are required, threaded inserts are provided in the holes into which the fasteners extend (only some of these inserts being shown in FIG. 2 in the interest of clarity).

A rectangular metal plate 65 is secured to the upper surface of the end wall 52 by fasteners 63. This plate, like the head portion 61 of the plate 58 overhangs the groove 48 in the body section 44. As best shown in FIG. 4, the overhanging portion of these plates bear against the surfaces 34 of the housing of a connector mounted in the tool and serve to hold the housing in the tool.

A channel-like groove 68 is provided on the underside of the cap section 46 of the housing section 46 and the plunger 42 is slidably contained in this groove, the base of the ram being supported by the upper surface of the plate 58. Legs 70 depend from the underside of the section 46 on each side of the groove 68 and rest on the floor of the depression 56 on each side of the leg 60 of the plate 58. The legs 70 have a snug fit between the sidewalls 57 of the depression and the side edges of the leg 60, the cap section being accurately located on the body section by virtue of this snug fit.

'Thecap section 46 is secured to the base section by a screw 72 which extends through the top of the cap section, through an elongated slot 74 on the ram 42, through a hole 73 in the plate 58, and into a hole 76 in the body portion of the housing, a threaded insert 78 being contained in this hole as previously described. The cap section 46 has a flange 80 which extends forwardly over the head portion 61 of the plate 58 and this flange has a centrally located hole 82 which is in align ment with the hole 61 in plate 58. A narrow slot 84 extends from this hole to the leading edge of the flange to permit removal of a previously inserted wire from the hole.

As shown in FIG. 4, the inserting plunger or ram 42 has a generally rectangular cross-section and has a metallic U-shaped insert integrally molded into its leading end. The upper leg 88 of this insert is co-planar with the upper surface of the ram and extends forwardly beyond the face or leading end of the ram. This upper leg has a central notch 90 which receives the wire and aids in pushing it into the terminal during an inserting operation. The lower leg 92 of insert 86 also extends beyond the end of the plunger and cooperates with the plate 61 to shear a wire during the inserting operation. The wire is pushed into the terminal by the leading end of the leg 92 and by two pushers 94, 96 which are integral with the plunger. The pusher member 94 is relatively narrow and is dimensioned to fit between the connecting strap portions 14 of the conductor receiving portion 8 of the terminal. It will be apparent from FIGS. 7 and 4 that this central pusher is spaced from the leg 92 and from the pusher 96 by distances such that the leading end of the ram can move past the strap positions 14 of the terminals so that the plate-like portions 10, 12 of the terminals are received between the pushers 96, 94 and between the wire pusher 94 and the leg 92.

A recess 98 is provided on the side 100 of the ram 42 and two teeth 102 are provided in this recess. A pawl 104, having an extension 106, is provided in a cavity 108 in a side portion 110 of the upper portion 46 of the housing. The pawl 104 has integral stub shafts 114 which are received in openings in the side portion 110 of the housing cap 46 and in a spacer plate 112 which is interposed between the side portion 110 and the upper surface 62 of the housing section 54. As shown in FIG. 3, pins 111 depend from the side portion 110 of the housing and are adapted to enter holes in the spacer 1 12.

Pawl 104 is biased in a counterclockwise direction as viewed in FIG. 3 by a spring 116 which has one end 117 thereof hooked to the pawl and has another end which extends through an opening 120 in the backwall of the housing section 110. A retainer 122 is fastened to the end 118 of the spring and bears against the backwall of the house so that the pawl can be swung in a clockwise direction with accompanying tensioning of the spring 116.

It will be apparent from the foregoing explanation that when the operator pushes the ram through the housing, the tooth 106 must move over the teeth 102 and the ram cannot be returned to its normal position until it moves past the second one or rearward one of the teeth 102.- This pawl and ratchet system thus serves as a full stroke compelling means which ensures that the wire will be fully inserted into the terminal during operation of the tool.

The rearward end of the'ram is provided with an end section 124 which extends laterally in opposite directions and which serves as a bearing or holding surface when the tool is used. A similar bearing surface 128 is provided on the front wall 52 of the housing in alignment with the surfaces of the extension 124. As will be explained more fully below, the technician will ordinarily place the surfaces 124 against the palm of his hand and curl his fingers over the surface 128 so that upon squeezing the tool, the ram 42 will be moved towards the front wall 52. The ram is resiliently biased rearwardly in the housing by a spring 126 which surrounds the ram and bears against the rearward side of the housing cap 46 and against the extension 124 on the ram. The forward stroke of the ram is limited by a shoulder 123 on the underside thereof which is adapted to bear against the rearwardly facing edge of the leg of the T-shaped plate 58 at the end of the forward stroke.

It is advantageous to provide a guide means for the short section of wire which is trimmed from the end of the conductor being inserted into a terminal in a connector. Accordingly, a channel-shaped guide chute 154 is provided which has ribs 156 on its sidewalls at its upper end. The upper ends of these ribs are enlarged to provide hooks 158 and the upper end of the guide chute is dimensioned to be received in a central opening in the body portion of the housing adjacent at the inner end of the groove 48. The sides 160 of this opening are provided with centrally located grooves having notches 162 at their upper ends which are adapted to receive the upper ends of the guide ribs 156. The web of the channel-shaped member 154 is slotted as shown at the member 157 so that the sidewall can be flexed towards each other while the chute is being assembled to the body portion of the housing.

Detent means are provided in the floor of the groove 48 for cooperation with ratchet teeth on the holder 50 as will be described below. This detent means comprises a resiliently biased detent member 166 having an integral post 168 on its underside which is received in a hole 173 in the floor of the slot or groove 48. A spring is interposed between the underside of the tooth 166 and the inner end of the hole 173. The lower end of the post 168 extends through a circular hole of smaller diameter than the hole 173 and has a spring retainer 174 on its end. The spring 172 thus biases the detent 166 upwardly but the detent can be depressed when the connector holder 40 is moved through the slot 48.

The connector holder 50 has a generally rectangular base 130 having a column 132 extending upwardly from its lefthand end as viewed in FIG. 2. This column has a rightwardly or inwardly extending arm 134. A flange 136 is provided on the other end of the base 130 and a similar arm 138 extends inwardly over the base from this flange. The opposed faces 140 of the arms 134, 138 are spaced apart by a distance substantially equal to, and slightly'less than, the distance between the sidewalls 141 of the rib portion 32 of the connector housing so that the housing can be pressed on the base 130 and will be resiliently gripped between the arms 134, 138.

Means are also provided to clamp a multi-conductor electrical cable 3 on the connector holder 50 while the conductors 2 of the cable are being connected or inserted into the terminals. This clamping means comprises a plate 142 which is spaced from the flange 136 and connected thereto by an integral gusset 144. The upper edges of the flange and the plate 142 are notched as shown at 146 so that the cable can. be nested on these upper edges as shown in FIG. 1. The cable is clamped by means of a molded plastic strap 148 having holes 150 adjacent to its ends adapted to receive cylindrical bosses 152 on the sides of the gusset plate as also shown in FIG. 1. The underside of the web or base 130 of the connector holder has a plurality of transverse extending grooves or teeth 164 which are adapted to receive the pointed upper end of the detent 166. The centers of these teeth are precisely located with references to the terminals in the connector so that a specific terminal can be aligned with the ram by moving the holder through the groove 48 until the detent 166 lodges in the corresponding tooth 164.

In use, and assuming that the technician wishes to connect all of the conductors 2 in a cable to the terminals in a connector, he first clamps the cable to the righthand end of the connector holder and positions the connector on the base 130 of the holder as shown in FIG. 1. He then slides the holder partially through the groove 48 so that the projecting edge of the plate 58 will be over the upper surface 34 of the housing and the plate 63 will extend over the surface 34 on the opposite side of the housing. He aligns the first terminal in the row which is proximate to the ram with the ram and then inserts the end of a wire through the hole 82 and through the hole 66 in the plate 58 so that the end of the wire will extend down into the chute 154 and between the sidewalls thereof. He then squeezes the tool to drive the ram from the position of HG. 4 to the position of FIG. 5 and during such movement of the ram, the wire will be pushed to the end of the hole 66 by the leading end of the plunger. The lower leg 92 of the insert 86 will shear the wire as it moves past the edge 66 of the hole and the scrap wire will drop downwardly through the chute 154. The terminal wire end will then be pushed rightwardly as viewed in FIG. 4 until it is fully inserted into the terminal as illustrated in FIGS. 5 and 7. The operator then releases his grip on the tool to allow the ram to return to its normal position. He then pushes the slide until the next adjacent terminal is in alignment with the ram and repeats the wire inserting operation discussed above.

It will be apparent from the foregoing that a tool in accordance with the invention is extremely compact and convenient to use and that most of the parts can be made of molded plastic. Extremely precise positioning of the terminals with respect to the ram can be achieved by virtue of the detent mechanism and any type or size of connector can be accepted if a suitably dimensioned connector holder is used.

Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made without departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by ay of illustration only.

What is claimed is:

1. An improvement to a hand tool for inserting conductors into the conductor-receiving portions of electrical contact terminals, said terminals being contained in an electrical device such as a multi-contact electrical connector, said hand tool being of the type comprising a frame, an inserting ram in said frame, said ram being reciprocable along a first predetermined path electrical device holding means on said frame for holding said electrical device at one end of said path, and indexing means or selectively indexing said electrical device along a second path which extends transversely of said first path thereby to permit said conductor-receiving portions of said terminals to be successively positioned at said one end of said first path whereby a conductor can be inserted into each of said conductor receiving portions, said improvement comprising:

first and second tool holding means for holding and activating said tool in the palm of the hand,

said first tool holding means comprising a first holding surface on said ram, said first surface extending laterally on each side of said ram,

said second tool holding means comprising a second holding surface integral with said frame and extending laterally in one each side thereof, said second surface extending beside said second path and transversely with respect to said first path, said second surface being in alignment with said first surface whereby, one of said holding surfaces can be placed against the palm of the hand and the other one of said surfaces can be cradled in the fingers of the hand, and upon squeezing said surfaces, said ram will be driven along said first path to insert a conductor into the conductor-receiving portion of the contact terminal in said electrical device which lies on said first path.

2. A hand tool as set forth in claim 1, said electrical device holding means comprising a separate holder having means on one side thereof for precisely locating said electrical device thereon, said frame having recess means extending therethrough transversely of said first path, said separate holder being slidable through said recess means.

3. A hand tool as set forth in claim 2, said indexing means comprising detent means effective between said frame and said separate holder.

5. A hand tool as set forth in claim 2. said separate holder having at one end thereof cable clamping means for clamping an electrical cable containing conductors which are to be connected to terminals in a connecting device mounted in said separate holder. 

1. An improvement to a hand tool for inserting conductors into the conductor-receiving portions of electrical contact terminals, said terminals being contained in an electrical device such as a multi-contact electrical connector, said hand tool being of the type comprising a frame, an inserting ram in said frame, said ram being reciprocable along a first predetermined path electrical device holding means on said frame for holding said electrical device at one end of said path, and indexing means or selectively indexing said electrical device along a second path which extends transversely of said first path thereby to permit said conductorreceiving portions of said terminals to be successively positioned at said one end of said first path wherEby a conductor can be inserted into each of said conductor receiving portions, said improvement comprising: first and second tool holding means for holding and activating said tool in the palm of the hand, said first tool holding means comprising a first holding surface on said ram, said first surface extending laterally on each side of said ram, said second tool holding means comprising a second holding surface integral with said frame and extending laterally in one each side thereof, said second surface extending beside said second path and transversely with respect to said first path, said second surface being in alignment with said first surface whereby, one of said holding surfaces can be placed against the palm of the hand and the other one of said surfaces can be cradled in the fingers of the hand, and upon squeezing said surfaces, said ram will be driven along said first path to insert a conductor into the conductor-receiving portion of the contact terminal in said electrical device which lies on said first path.
 2. A hand tool as set forth in claim 1, said electrical device holding means comprising a separate holder having means on one side thereof for precisely locating said electrical device thereon, said frame having recess means extending therethrough transversely of said first path, said separate holder being slidable through said recess means.
 3. A hand tool as set forth in claim 2, said indexing means comprising detent means effective between said frame and said separate holder.
 4. A hand tool as set forth in claim 3, said detent means comprising ratchet teeth on said separate holder on the side thereof which is opposite to said one side, said ratchet teeth being at locations corresponding to the locations in said electrical device, and said frame having a resiliently biased detent therein for engagement with said ratchet teeth.
 5. A hand tool as set forth in claim 2, said separate holder having at one end thereof cable clamping means for clamping an electrical cable containing conductors which are to be connected to terminals in a connecting device mounted in said separate holder. 